The wireless communication environment in a home or in an office typically includes a number of independently developed radio access technologies and standards. One of the communication standards currently being implemented in electronic equipment is near field communication (NFC). The use of NFC interfaces in electronic equipment provides portable devices with functions similar to those of non-contact integrated circuit cards (e.g., RFID cards).
Electronic equipment provided with NFC interfaces are typically capable of operating as radio frequency (RF) readers and/or writers to communicate with other NFC devices. A basic aspect of NFC is an usage of electromagnetic waves in a RF range and that a transmission of information contents is realized over a short distance only, for instance in a range of several centimeters.
RFID applications are widely used in many areas such as public traffic service, object tracking systems and home management. In an NFC or an RFID application, a transmitter of a proximity coupling device (PCD), also known as a reader, writer, or initiator, may use one of following three linear codes, followed by an amplitude modulation: (1) a Modified-Miller code used for type A NFC, (2) a non-return-to-zero (NRZ) code used in type B NFC, and (3) a Manchester code used in type F NFC.